@Kyxr
No, it's not. Yes, it is a guy persuing another guy but it's not like that... at least not to where its been translated. You never know with these things. Like Kuroshitsuji, it started out as a yaoi but quickly turned into the adventure story it so awesomely is.
Also, if it were BL it would state that it is.
The way to tell if the manga is yaoi from the front cover is if it looks like the guys are in a sexy, and beautiful (artistically from a photographers point of view) position.